The number density of free electrons in copper is nearly $8 \times 10^{28}\,m ^{-3} . A$ copper wire has its area of cross section $=2 \times 10^{-6}\,m ^2$ and is carrying a current of $3.2\,A$. The drift speed of the electrons is $.....\times 10^{-6}\,ms ^{-1}$.
  • A$125$
  • B$124$
  • C$123$
  • D$122$
JEE MAIN 2023, Easy
art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    In the following circuit diagram, $E = 4\,V, r = 1\,\Omega$ and $R = 45\, \Omega$, then  reading of the ammeter $A$ will be
    View Solution
  • 2
    A potentiometer wire is $100\,\, cm$ long and a constant potential difference is maintained across it. Two cells are connected in series first to support one another and then in opposite direction. The balance points are obtained at $50\,\, cm$ and $10\,\, cm$ from the positive end of the wire in the two cases. The ratio of emf's is 
    View Solution
  • 3
    The equivalent resistance of the arrangement of resistances shown in adjoining figure between the points $A$ and $B$ is ............... $ohm$ 
    View Solution
  • 4
    A car battery of $e.m.f$. $12\,V$ and internal resistance $5 \times {10^{ - 2}}\,\Omega $, receives a current of $60\; A$ from external source, then terminal voltage of battery is 
    View Solution
  • 5
    In previous problem, if the cell had been connected in parallel (instead of in series) which of the above graphs would have shown the relationship between total current $I$ and $n$?
    View Solution
  • 6
    The current flowing through the $1 \Omega$ resistor is $\frac{\mathrm{n}}{10} \ A. $ The value of $n$ is. . . . . . .
    View Solution
  • 7
    Three resistors having resistances $\mathrm{r}_{1}, \mathrm{r}_{2}$ and $\mathrm{r}_{3}$ are connected as shown in the given circuit. The ratio $\frac{i_{3}}{i_{1}}$ of currents in terms of resistances used in the circuit is :
    View Solution
  • 8
    Three copper rods are subjected to different potential difference. Compare the drift speed of electrons through them. Assume that all $3$ are at the same temperature.
      Length Diameter Potential difference
    $(A)$ $L$ $3d$ $V$
    $(B)$ $2L$ $d$ $2V$
    $(C)$ $3L$ $2d$ $2V$
    View Solution
  • 9
    Two cells are connected in opposition as shown. Cell $\mathrm{E}_1$ is of $8 \mathrm{~V}$ emf and $2 \ \Omega$ internal resistance; the cell $E_2$ is of $2 \mathrm{~V}$ emf and $4\  \Omega$ internal resistance. The terminal potential difference of cell $\mathrm{E}_2$ is:
    View Solution
  • 10
    The electric bulbs have tungsten filaments of same length. If one of them gives $60 \,watt$ and other $100\, watt$, then
    View Solution